In recent years, in organic electroluminescences, various solar cells, touch panels, mobile phones, electronic papers, and the like, transparent electrodes using a transparent conductive film are being eagerly investigated.
For example, organic photoelectric conversion or electric-optical conversion devices typified by electronic solar cells are usually fabricated by laminating materials on electrodes composed of a transparent conductive film. As for the transparent conductive film, though various conductive films such as metal thin films, metal oxide thin films, conductive nitride thin films, etc. are being investigated, metal oxide thin films are the mainstream at present because they are chiefly capable of making both light transmission properties and conductivity compatible with each other and are also excellent in terms of durability.
Above all, in particular, tin-doped indium oxide (ITO) is well balanced between light transmission properties and conductivity, and it is widely used (see Patent Document 1, etc.). However, following an increase of the area of a transparent electrode, a more reduction of the resistance is required, and ITO is still not sufficient yet in terms of conductivity.
On the other hand, there is proposed a sheet in which a metal-made fine mesh or grid is formed on a transparent base material such as PET, etc. (see Patent Document 2, etc.). There is a possibility of utilization of such a sheet as a transparent electrode because its translucency and conductivity can be controlled according to a design of the mesh (rate of opening determined by a pitch or line width). For example, there is disclosed a transparent conductive film having a conductive metal mesh layer and a transparent conductive layer composed of a conductive polymer compound such as polythiophene on at least one surface of a transparent base material sheet (see Patent Document 3, etc.).
Now, in the case of laminating layers composed of an organic element material, electronic devices have hitherto been manufactured by a vacuum vapor deposition method or a dry process analogous thereto, a wet process typified by coating, or a lamination process via a pressure-sensitive adhesive or adhesive layer (see Patent Document 4, etc.).
In such the lamination process, transparent electrode films and transparent conductive films having adhesiveness are desired; however, the conventional transparent conductive films involve a problem on a balance among transparency, adhesiveness, and low surface resistivity.
Then, it has been proposed to use, as a conductive component in a conductive adhesive composition, a conductive organic polymer compound such as polythiophene or derivatives thereof. More specifically, it has been proposed to manufacture an electronic device by a lamination process via a pressure-sensitive adhesive or adhesive layer containing a conductive organic polymer compound (see Patent Document 5, etc.).
However, in the lamination process through a pressure-sensitive adhesive layer containing a conductive organic polymer compound, the utilization was limited in an element application in which cleanliness and uniformity of an interface are important. In addition, there was involved such a problem that the performance of an electronic device is lowered, for example, the conductivity of the pressure-sensitive adhesive or adhesive layer is low, the carrier injection efficiency at the laminate interface is lowered, an adhesive force at the interface is low, and the like.